51. Menene alamomi daban-daban waɗanda ke nuna kwayoyin halitta masu guba da cutarwa a cikin ruwa?
Sai dai ƴan ƙaramar mahadi masu guba da cutarwa a cikin najasa gama gari (kamar phenols masu canzawa, da sauransu), yawancinsu suna da wahalar biodegrade kuma suna da illa sosai ga jikin ɗan adam, kamar man fetur, anionic surfactants (LAS). Organic Chlorine da organophosphorus magungunan kashe qwari, polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), high-molecular roba polymers (kamar robobi, roba roba, wucin gadi zaruruwa, da dai sauransu), man fetur da sauran Organic abubuwa.
Babban ma'aunin fitarwa na ƙasa GB 8978-1996 yana da ƙayyadaddun ƙa'idodi kan tattara najasa mai ɗauke da abubuwa masu guba da cutarwa da masana'antu daban-daban ke fitarwa. Ƙayyadaddun alamun ingancin ruwa sun haɗa da benzo (a) pyrene, man fetur, phenols masu canzawa, da magungunan kashe qwari na organophosphorus (ƙididdige su a P), tetrachloromethane, tetrachlorethylene, benzene, toluene, m-cresol da 36 wasu abubuwa. Masana'antu daban-daban suna da alamomin fitar da ruwa daban-daban waɗanda ke buƙatar sarrafawa. Ya kamata a kula da ko ma'aunin ingancin ruwa ya cika ka'idojin fitarwa na ƙasa bisa ƙayyadaddun abubuwan da kowace masana'anta ke fitarwa.
52.Nawa nau'ikan mahadi na phenolic ne a cikin ruwa?
Phenol wani nau'in hydroxyl ne na benzene, tare da rukuninsa na hydroxyl kai tsaye a haɗe zuwa zoben benzene. Dangane da adadin ƙungiyoyin hydroxyl da ke cikin zoben benzene, ana iya raba shi zuwa phenols na ɗaya (kamar phenol) da polyphenols. Dangane da ko zai iya canzawa da tururin ruwa, an raba shi zuwa phenol mai canzawa da phenol mara maras tabbas. Saboda haka, phenols ba kawai suna nufin phenol ba, har ma sun haɗa da sunan gaba ɗaya na phenolates wanda aka maye gurbinsu da hydroxyl, halogen, nitro, carboxyl, da dai sauransu a cikin ortho, meta da para matsayi.
Abubuwan da ake kira phenolic suna nufin benzene da haɗe-haɗen zobe na hydroxyl. Akwai iri da yawa. Gabaɗaya ana la'akari da cewa waɗanda ke da wurin tafasa a ƙasa da 230oC phenols ne masu canzawa, yayin da waɗanda ke da maki mai tafasa sama da 230oC ba phenols ne masu canzawa ba. Ƙunƙarar phenols a cikin ma'aunin ingancin ruwa yana nufin mahaɗan phenolic waɗanda zasu iya canzawa tare da tururin ruwa yayin distillation.
53. Menene hanyoyin da aka saba amfani da su don auna phenol mai canzawa?
Tun da ƙananan phenols nau'i ne na fili maimakon guda ɗaya, ko da an yi amfani da phenol a matsayin ma'auni, sakamakon zai bambanta idan an yi amfani da hanyoyin bincike daban-daban. Domin yin kwatankwacin sakamakon, dole ne a yi amfani da hanyar haɗin kai da ƙasar ta ayyana. Hanyoyin aunawa da aka saba amfani da su don phenol mai canzawa sune 4-aminoantipyrine spectrophotometry da aka ƙayyade a cikin GB 7490-87 da ƙarfin bromination da aka ƙayyade a GB 7491-87. Doka
4-Aminoantipyrine spectrophotometric Hanyar yana da ƙananan abubuwan tsangwama da mafi girman hankali, kuma ya dace don auna samfuran ruwa mai tsabta tare da abun ciki mai canzawa.<5mg>Hanyar bromination volumetric yana da sauƙi kuma mai sauƙi don aiki, kuma ya dace don ƙayyade adadin phenols masu canzawa a cikin ruwa mai tsabta na masana'antu> 10 mg / L ko ƙazanta daga masana'antun sarrafa ruwa na masana'antu. Babban ka'idar ita ce a cikin bayani tare da wuce haddi bromine, phenol da bromine suna haifar da tribromophenol, kuma suna kara haifar da bromotribromophenol. Ragowar bromine sai ya amsa tare da potassium iodide don sakin iodine kyauta, yayin da bromotribromophenol yana amsawa da potassium iodide don samar da tribromophenol da iodine kyauta. Sa'an nan kuma ana ba da iodin kyauta tare da maganin sodium thiosulfate, kuma ana iya ƙididdige abin da ke cikin phenol mai canzawa dangane da phenol dangane da amfaninsa.
54. Menene matakan kariya don auna phenol mai canzawa?
Tun da narkar da oxygen da sauran oxidants da microorganisms iya oxidize ko decompose phenolic mahadi, yin phenolic mahadi a cikin ruwa sosai m, hanyar ƙara acid (H3PO4) da kuma rage yawan zafin jiki ne yawanci amfani da su hana mataki na microorganisms, da kuma isasshe. an ƙara adadin sulfuric acid. Hanyar ferrous yana kawar da tasirin oxidants. Ko da an ɗauki matakan da ke sama, ya kamata a bincika samfuran ruwa tare da gwadawa a cikin sa'o'i 24, kuma samfuran ruwan dole ne a adana su a cikin kwalabe na gilashi maimakon kwantena filastik.
Ko da kuwa hanyar bromination volumetric ko hanyar 4-aminoantipyrine spectrophotometric, lokacin da samfurin ruwa ya ƙunshi oxidizing ko rage abubuwa, ions karfe, amines aromatic, mai da tars, da dai sauransu, zai yi tasiri akan daidaiton ma'auni. tsoma baki, dole ne a dauki matakan da suka dace don kawar da tasirinsa. Alal misali, ana iya cire oxidants ta ƙara ferrous sulfate ko sodium arsenite, ana iya cire sulfide ta hanyar ƙara sulfate na jan karfe a ƙarƙashin yanayin acidic, mai da kwalta za a iya cirewa ta hanyar cirewa da rabuwa tare da kaushi mai ƙarfi a ƙarƙashin yanayin alkaline mai ƙarfi. Rage abubuwa kamar sulfate da formaldehyde ana cire su ta hanyar fitar da su tare da kaushi na halitta a ƙarƙashin yanayin acidic da barin abubuwan ragewa a cikin ruwa. Lokacin yin nazarin najasa tare da ƙayyadaddun ƙayyadaddun kayan aiki, bayan tara wani ɗan lokaci na gwaninta, za a iya bayyana nau'in abubuwan da ke shiga tsakani, sa'an nan kuma za a iya kawar da nau'in abubuwan da ke shiga tsakani ta hanyar karuwa ko raguwa, kuma ana iya sauƙaƙe matakan bincike kamar yadda ya kamata. kamar yadda zai yiwu.
Ayyukan distillation muhimmin mataki ne a cikin ƙayyadaddun phenol mai canzawa. Domin ya kawar da phenol mai canzawa gaba ɗaya, ƙimar pH na samfurin da za a distilled ya kamata a daidaita shi zuwa kusan 4 (kewayon launi na methyl orange). Bugu da ƙari, tun da tsarin ƙaddamarwa na phenol mai sauƙi yana da jinkirin jinkirin, ƙarar distillate da aka tattara ya kamata ya zama daidai da girman samfurin asali da za a distilled, in ba haka ba za a shafi sakamakon ma'auni. Idan an gano distillate ya zama fari da turbid, ya kamata a sake kwashe shi a ƙarƙashin yanayin acidic. Idan distillate har yanzu fari da turbid a karo na biyu, yana iya zama cewa akwai mai da kwalta a cikin samfurin ruwa, kuma dole ne a gudanar da magani daidai.
Jimlar adadin da aka auna ta amfani da hanyar volumetric bromination shine darajar dangi, kuma dole ne a bi ka'idodin aiki da ƙayyadaddun ƙayyadaddun ƙa'idodin ƙasa, gami da adadin adadin ruwa da aka ƙara, zazzabi da lokacin amsawa, da sauransu. Bugu da ƙari, tribromophenol yana haɓaka cikin sauƙi encapsulate I2 don haka ya kamata a girgiza da ƙarfi yayin da ake gabatowa wurin titration.
55. Menene matakan kariya don amfani da 4-aminoantipyrine spectrophotometry don tantance phenols masu canzawa?
Lokacin amfani da 4-aminoantipyrine (4-AAP) spectrophotometry, duk ayyuka ya kamata a yi a cikin hurumin hayaki, kuma ya kamata a yi amfani da tsotsan injin tururi don kawar da mummunan tasirin benzene mai guba akan mai aiki. .
Haɓakawa a cikin ƙima mara kyau na reagent ya samo asali ne saboda dalilai kamar gurɓata ruwa a cikin ruwa mai narkewa, gilashin gilashi da sauran na'urorin gwaji, da kuma rashin daidaituwar abubuwan da ake cirewa saboda hauhawar zafin ɗakin, kuma galibi saboda 4-AAP reagent. , wanda ke da haɗari ga shayar da danshi, caking da oxidation. , don haka ya kamata a dauki matakan da suka dace don tabbatar da tsabtar 4-AAP. Ci gaban launi na halayen yana da sauƙin tasiri ta ƙimar pH, kuma ƙimar pH na maganin amsa dole ne a sarrafa shi sosai tsakanin 9.8 da 10.2.
Matsakaicin daidaitaccen bayani na phenol ba shi da kwanciyar hankali. Ya kamata a sanya daidaitaccen bayani mai ɗauke da 1 mg phenol a kowace ml a cikin firiji kuma ba za a iya amfani da shi ba fiye da kwanaki 30. Ya kamata a yi amfani da daidaitaccen bayani wanda ya ƙunshi 10 μg phenol a kowace ml a ranar shiri. Ya kamata a yi amfani da daidaitaccen bayani wanda ya ƙunshi 1 μg phenol a kowace ml bayan shiri. Yi amfani a cikin sa'o'i 2.
Tabbatar ƙara reagents don daidaitattun hanyoyin aiki, kuma girgiza da kyau bayan ƙara kowane reagent. Idan buffer ba a girgiza ko'ina ba bayan ƙara shi, ƙaddamarwar ammoniya a cikin maganin gwaji zai zama rashin daidaituwa, wanda zai shafi tasirin. Ammoniya mara tsabta na iya ƙara ƙimar mara komai fiye da sau 10. Idan ba a yi amfani da ammonia na dogon lokaci ba bayan buɗe kwalban, ya kamata a distilled kafin amfani.
Jan rini na aminoantipyrine da aka samar ya tsaya tsayin daka na kusan mintuna 30 a cikin maganin ruwa mai ruwa, kuma zai iya zama karko na sa'o'i 4 bayan an cire shi cikin chloroform. Idan lokacin ya yi tsayi sosai, launi zai canza daga ja zuwa rawaya. Idan launin maraƙin ya yi duhu sosai saboda ƙazantar 4-aminoantipyrine, ana iya amfani da ma'aunin tsayin tsayin 490nm don haɓaka daidaiton auna. 4-Lokacin da aminoantibi ya kasance najasa, ana iya narkar da shi a cikin methanol, sannan a tace shi a sake shi da carbon da aka kunna don tace shi.
Lokacin aikawa: Nuwamba-23-2023
